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| author | Yufen Yu <yuyufen@huawei.com> | 2020-07-18 12:29:09 +0300 |
|---|---|---|
| committer | Song Liu <songliubraving@fb.com> | 2020-07-22 03:18:22 +0300 |
| commit | 3b5408b98e4db62b322f8516a0d08f95f197c42f (patch) | |
| tree | 30f49a337e78de8f331802cdbfe37eca4e92faa1 /drivers/md/raid5.c | |
| parent | e236858243d7a8e0ac60972d2f9522146088a736 (diff) | |
| download | linux-3b5408b98e4db62b322f8516a0d08f95f197c42f.tar.xz | |
md/raid5: support config stripe_size by sysfs entry
Adding a new 'stripe_size' sysfs entry to set and show stripe_size.
stripe_size should not be bigger than PAGE_SIZE, and it requires to
be multiple of 4096. We can adjust stripe_size by writing value into
sysfs entry, likely, set stripe_size as 16KB:
echo 16384 > /sys/block/md1/md/stripe_size
Show current stripe_size value:
cat /sys/block/md1/md/stripe_size
For PAGE_SIZE is equal to 4096, 'stripe_size' can just be read.
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Diffstat (limited to 'drivers/md/raid5.c')
| -rw-r--r-- | drivers/md/raid5.c | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 60cfa397f2d6..40961dd1777b 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -6503,6 +6503,77 @@ raid5_rmw_level = __ATTR(rmw_level, S_IRUGO | S_IWUSR, raid5_show_rmw_level, raid5_store_rmw_level); +static ssize_t +raid5_show_stripe_size(struct mddev *mddev, char *page) +{ + struct r5conf *conf; + int ret = 0; + + spin_lock(&mddev->lock); + conf = mddev->private; + if (conf) + ret = sprintf(page, "%lu\n", RAID5_STRIPE_SIZE(conf)); + spin_unlock(&mddev->lock); + return ret; +} + +#if PAGE_SIZE != DEFAULT_STRIPE_SIZE +static ssize_t +raid5_store_stripe_size(struct mddev *mddev, const char *page, size_t len) +{ + struct r5conf *conf; + unsigned long new; + int err; + + if (len >= PAGE_SIZE) + return -EINVAL; + if (kstrtoul(page, 10, &new)) + return -EINVAL; + + /* + * The value should not be bigger than PAGE_SIZE. It requires to + * be multiple of DEFAULT_STRIPE_SIZE. + */ + if (new % DEFAULT_STRIPE_SIZE != 0 || new > PAGE_SIZE || new == 0) + return -EINVAL; + + err = mddev_lock(mddev); + if (err) + return err; + + conf = mddev->private; + if (!conf) { + err = -ENODEV; + goto out_unlock; + } + + if (new == conf->stripe_size) + goto out_unlock; + + pr_debug("md/raid: change stripe_size from %lu to %lu\n", + conf->stripe_size, new); + + mddev_suspend(mddev); + conf->stripe_size = new; + conf->stripe_shift = ilog2(new) - 9; + conf->stripe_sectors = new >> 9; + mddev_resume(mddev); + +out_unlock: + mddev_unlock(mddev); + return err ?: len; +} + +static struct md_sysfs_entry +raid5_stripe_size = __ATTR(stripe_size, 0644, + raid5_show_stripe_size, + raid5_store_stripe_size); +#else +static struct md_sysfs_entry +raid5_stripe_size = __ATTR(stripe_size, 0444, + raid5_show_stripe_size, + NULL); +#endif static ssize_t raid5_show_preread_threshold(struct mddev *mddev, char *page) @@ -6691,6 +6762,7 @@ static struct attribute *raid5_attrs[] = { &raid5_group_thread_cnt.attr, &raid5_skip_copy.attr, &raid5_rmw_level.attr, + &raid5_stripe_size.attr, &r5c_journal_mode.attr, &ppl_write_hint.attr, NULL, |